The present invention relates to a propulsion device for a swimmer, and particularly to a propulsion device designed to increase the propulsion efficiency of a swimmer.
In the design of a propulsion device for a swimmer, the applicant feels there are important criteria that need to be considered. For example, efficiency of the device is an important consideration. Specifically, as a swimmer kicks, it is important to provide useful thrust while minimizing drag forces that can cause undesirable resistance. In addition, a propulsion device should exploit the strengths of the swimmer's body and account for its weaknesses. Specifically, the device should account for the strenuous forces and moments that are applied to the swimmer's foot and ankle and also minimize the risk of overworking the hamstring and calf muscles of the swimmer's legs. Thus, it is desirable for the device to not overtax these vulnerable parts of the swimmer's body, while at the same time exploiting strong muscles like the quadriceps.
Thus, a principal objective of the present invention is to provide a swimmer with a propulsion apparatus that takes into account the differences in power available on up-strokes and down-strokes so as not to overtax any of the swimmer's muscle groups. Another objective is to provide a propulsion device designed such that forces and moments applied to the user's feet and ankles by the fin be relatively small to reduce physical strain on the swimmer.